Toshiba TB-FC30E is a toner-collection container for compatible Toshiba e-STUDIO multifunction printers. It collects residual toner as part of the printer’s toner handling system; it is a waste-toner container, not a toner cartridge.
Toshiba lists the e-STUDIO 2050C, 2550C, 2051C and 2551C, as well as the 2000AC, 2500AC, 2010AC and 2510AC, as compatible models. The part is intended for replacing the toner collector in these machines.
Toshiba provides a replacement guide for this specific reference. Its purpose is straightforward: to restore the toner-collection component when it needs replacement, so the printer can continue operating with the specified collector in place.